What Homeowners Need to Know

Water Quality in Middleton, Wisconsin

Middleton, WI is a growing suburb located just west of Madison in Dane County. Its water utility serves more than 20,000 residents, sourcing water primarily from municipal groundwater wells. Like other communities in south-central Wisconsin, Middleton experiences hard water and recurring issues with nitrate runoff and chlorine-based disinfection byproducts. While water meets legal limits, several contaminants have exceeded EWG health-based benchmarks, raising concerns about long-term exposure for families.

If you live in Middleton, Wisconsin, and are wondering what’s really in your tap water, you’re not alone. While the local utility provides water that complies with federal regulations, findings from the Environmental Working Group (EWG) reveal a different story. Eight contaminants in Middleton’s water exceed EWG’s stricter health-based guidelines—including nitrate, radium, and disinfection byproducts like TTHMs and HAA5. These substances have been linked to health concerns such as bladder cancer, thyroid dysfunction, and developmental delays in children. Middleton’s water is sourced from groundwater wells that are vulnerable to both natural and agricultural pollutants. Elevated nitrate levels suggest runoff from nearby farming operations. Meanwhile, radium and strontium occur naturally in the local bedrock and are difficult to remove without targeted treatment. Residents also report frequent hard water problems, staining on fixtures, and occasional chemical odors—likely stemming from chlorination and excessive minerals. At Water Doctors, we understand Middleton’s water profile because we’ve been testing and treating homes across Dane County for decades. Our no-cost in-home water test will identify local problem contaminants and give you clear, expert recommendations tailored to your home. Whether you’re concerned about health risks or just want better-tasting water, we’re here to help you find the right solution.

Know what’s in your Cedarburg WI tap water – EWG water quality awareness graphic

Contaminants of Concern in Middleton’s Water

EWG.org Research (via ZIP Code for Middleton, WI – 53562)

According to the Environmental Working Group (EWG), Middleton’s water utility (Public Water System ID: WI1130242) has 15 contaminants that exceed EWG health guidelines, with 32 total contaminants detected. These include disinfection byproducts, industrial solvents, agricultural runoff, PFAS, and radioactive elements.

Total contaminants exceeding health guidelines: 15

Top 10 Contaminants Detected (with tested levels):

Bromodichloromethane – 2.07 ppb (34× EWG guideline)
Chloroform – 4.66 ppb (12×)
Chromium (hexavalent) – 0.746 ppb (37×)
Dibromoacetic acid – 0.349 ppb (12×)
Dibromochloromethane – 1.14 ppb (11×)
Dichloroacetic acid – 1.86 ppb (9.3×)
Haloacetic acids (HAA5) – 3.83 ppb (38×)
Haloacetic acids (HAA9) – 6.58 ppb (110×)
Nitrate – 2.09 ppm (15×)
Total trihalomethanes (TTHMs) – 9.36 ppb (62×)

Key Notes on Water Findings:

Disinfection byproducts (TTHMs, HAA5, HAA9) appear at levels far above EWG’s health benchmarks and are associated with increased cancer risks.
PFAS compounds like PFHxS and total PFOS/PFOA are present in trace amounts but exceed EWG guidelines by large margins (45×–87×), raising concerns about endocrine and reproductive harm.
Chromium (hexavalent) and nitrate are present due to industrial and agricultural sources, and are linked to cancer and developmental issues.
Radium (combined 226 & 228) at 1.65 pCi/L (33× guideline) highlights naturally occurring radioactive exposure from local geology.
Middleton’s water is legally compliant under federal standards, but exceeds EWG’s more protective thresholds in key health categories. Residents should consider multi-stage filtration such as reverse osmosis for the most effective contaminant reduction.

View the EWG.org report for Middleton

Solutions to Common Issues

Choosing the Right Water Treatment for Your Home

Not all water is the same and neither are the solutions. Whether your water comes from a city supply or a private well, it can carry different minerals, chemicals, or contaminants that affect your home and health.

That’s why it’s important to look at all four key options:

Water softeners for hard water problems

Whole house filters for chlorine, odors, and sediment

Reverse osmosis systems for safe, great-tasting drinking water

Iron filters for rust stains and rotten egg smells

Your water source and the issues it brings will help determine which system (or combination) is right for you.

Water Softener

Hard water has minerals like calcium and magnesium that cause issues around your home. A water softener removes them for cleaner, better-feeling water.

Hard water can:

Leave spots on dishes
Make soap and shampoo less effective
Cause buildup on faucets and showerheads
Shorten the life of appliances
Dry out your skin and hair

A water softener:

Removes hard minerals
Helps soap work better
Protects appliances
Makes water feel soft on skin

If you see signs of hard water, a softener is a smart fix.

Water Softeners

Drinking Water System

Even if your tap water looks clean, it can still contain dissolved solids, chemicals, or contaminants you don’t want to drink. Reverse osmosis gives you highly purified water, right at the tap.

Unfiltered drinking water can have:

Chlorine, lead, or other chemicals
Nitrates, fluoride, or heavy metals
Cloudiness or bad taste
Pollutants from old pipes or plumbing

A reverse osmosis system:

Removes up to 99% of contaminants
Improves taste, clarity, and odor
Gives you bottled-quality water at home
Fits neatly under the kitchen sink

If you want cleaner, safer, better-tasting drinking water, RO is the gold standard.

Drinking Water Systems

Need an Iron Filter

If your water leaves orange stains or smells like metal or rotten eggs, iron could be the problem. An iron filter removes it before it damages your home.

Iron in water can:

Leave orange or brown stains in sinks, tubs, and toilets
Make water smell metallic or like rotten eggs (if sulfur is present)
Clog plumbing and damage appliances
Affect the taste of your water and food
Turn laundry yellow or dingy

An iron filter:

Removes iron, manganese, and sulfur odors
Protects pipes, water heaters, and fixtures
Stops staining and metallic smells
Keeps water clear and fresh

If your water looks rusty or smells off, an iron filter can make a big difference.

Whole House Water Filter

Tap water can carry things you don’t want—like chlorine, sediment, rust, or even odd tastes and smells. A whole house filter cleans the water before it reaches any faucet.

Unfiltered water can:

Smell or taste bad
Leave stains in sinks, tubs, and toilets
Carry chlorine or other chemicals
Irritate skin or worsen allergies
Let sediment build up in pipes and appliances

A whole house filter:

Removes chlorine, rust, dirt, and odors
Improves water taste and smell
Protects pipes, fixtures, and appliances
Provides clean water from every tap

Iron Filters & Whole Home Systems

Expert Advice, Exacting Science.

Get a Free Water Test in Middleton

Wondering what’s in your water? Schedule a free in-home water test and get professional insight into your home’s water quality. Our local team will test your water and recommend the right solution based on your results.

No pressure. Just clear answers and better water.

Call (262) 549-7733 or use our easy online scheduler now!

Why Middleton Homeowners Choose Water Doctors

Middleton families deserve clean, safe water they can trust. Schedule your free in-home water test with Water Doctors and get answers in minutes—not days. We test for Middleton’s top water concerns including nitrate, radium, disinfection byproducts, and mineral hardness. After testing, our specialists explain your results and offer custom treatment options to fit your home, budget, and health goals. Whether it’s a water softener, filtration system, or advanced reverse osmosis, we’ll help you take control of your water quality. Book your no-obligation test today and protect what matters most.

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